Drinking water purification device

ABSTRACT

A fast acting water purification system containing a source of silver ions which is suitable for use in personal or household water containers, where the non-potable water may contain halides or other materials that limit the solubility of silver in the non-potable water, with the purification agent including a source of silver ions and a compound containing a hydantoin ring increase the presence of silver ions in the non-potable water to a level sufficient to quickly kill harmful microorganisms in the non-potable water without the need to add additional biocides to the non-potable water or pretreat the non-potable water.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. application Ser. No. 14/593,836;filed Jan. 9, 2015 (pending), which is a continuation-in-part of U.S.application Ser. No. 13/987,789; filed Sep. 3, 2013 (abandoned), whichis a division of U.S. application Ser. No. 12/803,966 filed Jul. 9, 2010(now U.S. Pat. No. 8,591,735), which is a continuation-in-part of U.S.application Ser. No. 12/386,074 filed Apr. 14, 2009 (abandoned), whichis a continuation-in-part of U.S. application Ser. No. 12/315,285 filedDec. 2, 2008 (now U.S. Pat. No. 7,875,191) which is acontinuation-in-part of U.S. application Ser. No. 12/001,351 filed Dec.11, 2007 (abandoned), which is a continuation of application Ser. No.11/999,654 filed on Dec. 6, 2007 (now U.S. Pat. No. 7,501,067), which isa division of application Ser. No. 10/928,668 filed on Aug. 26, 2004,(now U.S. Pat. No. 7,347,934).

FIELD OF THE INVENTION

This invention relates generally to water purification and, morespecifically, to purifying small amounts of non-potable water inportable containers or in household containers where the non-potablewater may contain compounds that inhibit the effectiveness of the waterpurification material.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

None

REFERENCE TO A MICROFICHE APPENDIX

None

BACKGROUND OF THE INVENTION

The purification of small amounts of non-recreational and non-potablewater for individuals or households has been accomplished throughvarious methods. It is noted that the volume non-potable water intendedfor purification for the present invention may be defined as a volume ofnon-potable water that is generally not enough for bathing or swimmingin and may generally comprise a volume of 15 gallons or less. Somemethods for purifying small amounts of non-recreational and non-potablewater for individuals or households use involve pumping water through afilter to remove harmful bacteria while still other methods usechemicals such as halogens including chlorine, bromine and iodine. Somemethods, which use a source of silver ions as a disinfectant, requireone to pretreat the water in order to use silver ions purify the water.

One of the difficulties in creating potable water in small amounts isthe need to quickly generate potable water from non-potable water. U.S.Pat. No. 6,010,626 shows a pump that quickly generates potable water byforcing nonpotable water through a filter to remove bacteria and otherdebris. While such devices can work effectively for filtering outcertain types of bacteria they usually require extensive hand pumping togenerate a small amount of potable water since a large force is requiredto force the water through the small pores in the filter. A variety ofdifferent methods and apparatus are used to render non-potable waterpotable as evidenced by the following patents:

U.S. Pat. No. 4,894,154 shows an example of an individual portable watertreatment device that uses a pleated membrane-filtering cartridge.

U.S. Pat. No. 7,390,343 shows a device for removing harmful organismsfrom non-potable water with nano alumina fibers having particles ofmetals such as silver, copper or zinc deposited on the nano aluminafibers.

U.S. Pat. No. 4,349,512 shows an improved bacteriostatic filter mediafor home use that uses a bacteriostatic filter media comprising silvertreated cellulose and powdered carbon.

U.S. Pat. No. 4,267,455 shows another type of a water purificationdevice that uses UV tubes that extend through a chamber in the vessel.

U.S. Pat. No. 7,441,665 discloses a water purification cartridge for usein a gravity feed filtration discloses the use of a water purificationmedium that may include a halogenated polystyrene hydantoin, ahalogenated polymeric sulfonamide resins, a halogenated hydantoinsiloxane and a halogenated polystyrene traiznedione.

U.S. Pat. No. 4,695,379 discloses a water treatment bottle that includesa cap that can be placed on a bottle with the cap including a tube thatcontains a water treatment material such as carbon, silver impregnatedcoral sand, ion exchange resins to remove contaminants normally presentin tap water.

U.S. Pat. No. 4,198,296 shows pretreating the water to remove halideions so that the silver ions from the silver activated charcoal mediacan disinfect the water.

Some of the difficulties with the aforedescribed devices and methods arethat some types of filtration device require considerable work on partof the user to generate potable water thus discouraging their use. Stillothers require an extended length of time for the purification agent torender the water potable and still others require pretreatment of thewater before the water can be disinfected.

SUMMARY OF THE INVENTION

A fast acting water purification system containing a source of silverions which is suitable for use in personal or household water containerswith the water containers, having a volume and weight when filled, areportable by a single user preferably without the aide of a machine wherethe non-potable water may contain halides or other materials that limitthe solubility of silver in the non-potable water, with the purificationagent including a source of silver ions and a compound containing ahydantoin ring whereby the compound containing a hydantoin ring is addedto increase the solubility of silver ions in a body of water above thenatural solubility of silver ions in the non-potable water to therebyincrease the presence of silver ions in the non-potable water to a levelsufficient to quickly kill harmful microorganisms in the non-potablewater without the need to add additional biocides to the non-potablewater or pretreat the non-potable water.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial sectional view of a hand held water purificationdevice;

FIG. 2 is an exploded view of the hand held water purification device ofFIG. 1;

FIG. 3 is another embodiment of a hand held water purification device;

FIG. 4 shows a water purification member for placement in a container toobtain potable water;

FIG. 5 shows an alternate embodiment of water purification for on-the-gogenerating of small amounts of potable water;

FIG. 6 shows a container containing a tablet containing silver and ahydantoin for generating a container of potable water;

FIG. 7 shows a household container including a water purificationmaterial for generating sufficient potable water for a small household;

FIG. 8 is a partial sectional view of a dispenser holding a waterpurification material; and

FIG. 9 shows a water purification that converts non-potable water topotable water by pumping the non-potable water through the waterpurification material.

DESCRIPTION OF THE PREFERRED EMBODIMENT

While a source of silver ions has been widely used as a water-purifyingagent in various water purifying applications the limitation of thenatural solubility of silver in the non-potable water can adverselyaffect the ability of the silver to quickly kill harmful organisms inthe non-potable water. For example, because of the limited solubility ofsilver in water one may require an extended contact time of the silverions before the harmful microorganisms in the water are killed. In somecases the natural solubility of silver in the nonpotable water may beinsufficient to purify the water since the rate of microorganisms growthmay exceed the potential kill rate of the silver based waterpurification agent. In these cases other biocidal agents have been usedin conjunction with silver to kill harmful organisms and in still othercases halides or halogens that may interact with the silver ions must beremoved from the non-potable water before the silver ion basedpurification agent can be used to disinfect the water.

FIG. 1 shows an example of a hand held water purifier 10 comprising aportable container 11 having a cover or cap 12 with a drinking tube 13extending through the cap 12 and into a chamber 18. Located in chamber18 is the water purification material, which is contained within housing15. Container 11 may be a typical polymer plastic water bottle with ascrew top cap that is sufficiently small to allow one to carry thebottle as a person goes about their daily activities. Usually, suchcontainers contain a quart or less of water which enables them to beeasily carried from place to place. The screw top cap on the containerpermits one to obtain quick access to chamber 18 to allow one toperiodical refill the container with non-potable water once the potablewater in the container has been consumed. A feature of the drinking tube13 is that it allows one to draw potable water on demand from thechamber 18. In this example of the invention the non-potable water inthe container 11 can be quickly purified i.e. on the go by the waterpurification material located in housing 15 even as water is being drawnthrough drinking tube 13.

FIG. 2 shows the hand held water purifier 10 of FIG. 1 in an explodedview with a lower portion of a drinking tube 13 and housing 15 insection view. As can be seen the water purification material 17, whichincludes a source of silver ions, is retained in the in the lower end ofhousing 15 with the water purification material 17 having an exposedface 17 a for contact with nonpotable water placed in container 11. Thewater purification material 17 may be supported on an inert porouscarrier to permit water to flow threrethrough. Positioned downstream andin series with the water purification material 17 is a filter media 16which for example may include carbon particles or an ion exchange resin.In operation of the hand held water purification device 10 a person cangrasp container 11 in one hand and suck on tube 13 to draw water fromcontainer 11 through the water purification material 17, filter 16 andtube 13. In the example shown the water purification material 17includes a source of silver ions such as silver chloride, which issupported on a carrier. The carrier may be either a solid or porousstructure that is suitable for securing the silver chloride thereto,typically by an adhesive or the like which allows the silver ions to bereleased into the nonpotable water. In addition to the source of silverions in the water purification material 17 the water purificationmaterial includes a compound containing a hydantoin ring where thecompound containing the hydantoin ring may or may not have any biocidalproperties. As an option a filter media 16 of a selected pore size maybe located downstream of the water purification material to removeorganic particles or other types of larger particles that may be presentin the non-potable water. Although silver chloride is described as asource of silver ions other sources of silver ions may be used includingsilver metals without departing from the spirit and scope of theinvention described herein.

In the conventional process of purifying water it is known theavailability of silver ions for killing harmful microorganisms islimited by the natural solubility of the silver ions in water. That is,during the water purification phase the silver ions, which are graduallyconsumed in the water purification process, are replaced by fresh silverions, which are available from a source of silver ions in the water.Replacing the spent silver ions with fresh silver ions allows one tomaintain the level of available silver ions at the natural silver ionsolubility level. In general, the lower the solubility of silver inwater the longer the time needed for the silver ions to kill harmfulorganisms in the water since at any moment there are limited amounts ofsilver ions available to kill harmful organisms. Thus a limiting factorin water purification using silver ions may be the time required topurify the water in the container because of the limited availability offresh silver ions to replace the spent silver ions. In other cases thenatural solubility of silver ions in the non-potable water may beinsufficient to purify the water since the level of silver ions may beinadequate to overcome the growth of microorganisms. The addition of acompound containing a hydantoin ring, such as dimethylhydantoin (DMH),increases the solubility of silver in water and hence the quantity ofsilver ions present in the water even though the compound of itself mayhave no biocidal properties. That is the compound containing a hydantoinring when used alone lacks the ability to purify water.

Increasing the level of silver ions in the water reduces the time tobring the water to a purified stated since more silver ions areimmediately available for killing unwanted microorganisms. For example,with the invention described herein one can maintain the level of silverions in water at levels 2 to 3 times greater than is normally foundwhere silver ions are used as the sole water purification agent byadding DMH to the water to increase the solubility of silver ions in thewater and hence the ability to rid the water of harmful microorganisms.Thus, the addition of DMH to the water allows one to maintain a higherlevel of silver ions in the water, which permits the consumed silverions to be quickly replaced with fresh silver ions from the source ofsilver ions in the non-potable water which in turn reduces the time tobring the non-potable water to a potable state. The level of solubilityof silver in non-potable water may be limited by a number of factorsincluding the presence of halides in the non-potable water. In additionthe presence of other materials limit the solubility of silver in thenon-potable water. With the invention described herein one can increasethe level of silver ions in the non-potable water to levels that aresuch that the source of silver ions is the sole means for quickly andeffectively rendering non-potable water potable.

To avoid the possibility of skin discoloration due to argosies the EPAhas adopted 50 ppb or less of silver as an acceptable level of silverfor potable drinking water, however, in some countries the levels ofsilver are not limited since the adverse effects of consuming nonpotable water are considerably greater than the cosmetic effects of skindiscoloration due to argosies. In the event one wants to lower the levelof silver ions in the water after the water has been purified but beforethe water is ingested the purified water can be directed through afilter media such as an ion exchange medium to remove silver ions orbring the level of silver ions down to levels of 50 ppb or less.

In the invention described herein one can limit the concentration orsolubility of silver by controlling the concentration of DMH in thewater. For most applications a concentration of 5 ppm DMH is sufficientto increases the solubility of silver to levels that will quickly andeffectively kill bacteria, however, the concentration of DMH and theavailability of silver may be selected depending on the end use. Forexample one may add sufficient DMH to maintain the solubility of silverless than 50 ppb which maintains the concentration of silver belowcurrent EPA guidelines or one may add sufficient DMH to maintain thesilver ion concentration in excess of 50 ppb.

The use of silver chloride together with a compound containing ahydantoin ring creates a water purification material 17 that increasesthe solubility of silver ions in water and hence the ability of thesilver ions to kill harmful organisms without the addition of additionalwater purification agents even though the compound containing thehydantoin ring may lack any biocidal properties. A suitable compoundcontaining a hydantoin ring for enhancing the solubility of the silveris Dimethylhydantoin (DMH) although other compounds contain a hydantoinring may be used. An advantage in use of DMH is that DMH is not known tocontain any complexes that may be harmful if consumed. Another suitablehydantoin which lacks harmful complexes is glycolylurea.

In the example of FIG. 2 the housing includes an optional filter media16 which may be carbon. Carbon filters are generally used to improve thetaste of water by removing unwanted materials from the water. The carbonfilter may comprise particles or granules of carbon selected by size soas to block passage of particles exceeding a certain dimension. Otherexamples of filter media 16 that may be used include ion exchangeresins. An advantage of an ion exchange resin is it provides aconvenient way to prevent the flow of silver ions into the drinking tube13 since the silver ions can be trapped by the ion exchange resin infilter 16. Thus in one example of the invention a filter media 16 may beused to limit the level of silver ions in the potable water which isbeing ingested through drinking tube 13.

An advantage of the described use of a water purification materialutilizing DMH is that it that the level of silver ions in the containercontaining non-potable water can be elevated to levels sufficient toquickly and effectively kill harmful organisms and thus eliminate theneed for supplemental water purification agents or the need to pretreatthe non-potable water. Thus, through control of the level of silver ionsin the water by the addition of DMH one can enhance the solubility ofsilver to thereby increase the effectiveness of the water purificationmaterial. Since the water purification material with a source of silverions and the compound containing a hydantoin ring such as DMH caneffectively kill harmful organisms in the water the use of filter media16 to remove silver ions becomes option which may be dependent on theneeds, likes or dislikes of the user.

While it is understood that in some cases the normal silver solubilityin the non-potable water may be sufficient to maintain low bacteriallevels if sufficient contact time is available. In other cases one maywant to maintain a higher level of silver ions to more quickly andeffectively bring the non-potable water in the container to a potablestate by increasing the solubility of silver in the non-potable water.For example, with one type of non-potable water maintaining a level ofsilver ions at 10-15 ppb may quickly and effectively kill bacteria andother harmful organism including viruses. In other types of non-potablewater having higher bacteria levels one may have to increase the levelof silver ions in the potable water to levels in excess 100 ppb in orderto obtain a quick kill of harmful organisms. In both cases one canelevate the level of silver ions in the body of water and hence thebiocidal effectiveness of the water purification material by increasingthe solubility of silver in the body of water through the addition of acompound containing a hydantoin ring even though the compound containingthe hydantoin ring may or may not have any biocidal properties. Ingeneral increasing the level of the compound containing a hydantoin ringincreases the solubility of silver in the body of water. Thus a user hasthe option of selecting and controlling the level of silver ions in thenon-potable water by controlling the amount of the compound containing ahydantoin ring in the presence of non-potable water. This featureenables the water purification materials to be used on a variety ofdifferent types of non-potable water, some which may require extensivepurification and others, which may require minimal purification.

FIG. 3 shows an example of another embodiment of a hand held waterpurifier 40 that includes a portable container 41, which is suitable forholding in a user's hand. The water purification material 42 is locatedon the bottom of the container and typically comprises a source ofsilver ions such as silver chloride with a hydantoin such as DMH togenerate levels of silver ions sufficient to maintain the water in theportable container 41 free of bacteria and other harmful organisms. Touse the hand held water device 40 the user draws water into his or hermouth through the tube 44 that extends into the chamber 45 whichcontains the water which is being rid of harmful organisms by thepurification agent in the water purification material 42. In thisapplication an additional filter is not used and the water purificationagent in the water purification material 42 is affixed to the inside ofthe container to allow for repeated refilling of the water container.

FIG. 4 shows a cross sectional view of another example of a waterpurification device. Reference numeral 20 identifies a lower portion ofa portable container which contains a water purification device 27that's includes a drinking tube 29 that is connected to a pleated filter23 for removing organic matter. Filter 23 also includes a source ofsilver ions such as silver chloride 21 as well as a compound 22containing a hydantoin ring. The source of silver ions and the compoundcontaining the hydantoin ring are dispersed over the surface of thefilter 23. In this example the user draws drinking water through tube 25with the pleated filter 23 removing unwanted particles of material fromthe drinking water at the same time the water is being purified by thepresence of silver ions.

FIG. 5 shows an example of another water purification device or portablecontainer 30 that can be placed in an open source of water with thewater being purified as it is drawn through filter media 32. Filtermedia 32 includes a source of silver ions and a compound containing ahydantoin ring. In this example the filter media 32 is located in thelower end of an outlet housing 31 to enable the water purificationmaterial to come into direct contact with the non-potable water beforeit is drawn into drinking tube 35, which extends from the upper end ofhousing 31. The upper end of housing 31 may include a filter media, forexample, a carbon filter 33 to improve the taste of the water byremoving organic material from the water. In operation of waterpurification device 30 water is drawn through filter media 32 carbonfilter 33 and into plenum chamber 34 where it is drawn through tube 35to be ingested by the user. This type of water purification devicepermits a user to insert the water purification device directly intoanother water container or an open source of water such as a lake orstream to thereby quickly kill the harmful organisms before they can beingested. While the device shown in FIG. 5 is used with a carbon filter33 the device may be used without the carbon filter 33 at the user'soption.

Thus FIG. 5 discloses a method of purifying water immediately prior toconsumption of the water by introducing a non-potable water, where thenon-potable water may contain halides, into a housing 31 and bringingthe non-potable water into contact with a source of silver ions and acompound containing a hydantoin ring which is retained in porous filtermedia 32 by sucking on drinking tube 35. The filter media 32 increasesthe natural water solubility of silver ions in the non-potable water tothereby quickly convert the non-potable water into potable water byexposing the non-potable water to the source of silver ions and thecompound containing a hydantoin ring which are retained in filter media32. The water purification occurring prior to consuming the potablewater by drawing the water through the filter media 33 and into chamber34 where it can be made available for consumption.

FIG. 6 shows another example of a hand held water purifier comprising aportable container 50 having a removable cover 51 with a pellet ortablet 52 therein that in one example contains a source of silver ionsand a compound containing a hydantoin ring. A suitable material for thepellet or tablet may be silver chloride and a suitable compoundcontaining a hydantoin ring may be DMH. In this example the pellet maycontains just enough water purification materials to purifier a singlecontainer of non-potable water or if desired the pellet may besufficiently large so that the portable container 50 can be refilledmultiple times. In some cases the pellet or tablet may be dissolvable inwater. While a large number of compounds containing a hydantoin ring areavailable some of which contain halogens which are also effective inkilling harmful organisms an advantage of the use of DMH is that itlimits the types of water purification agents in the water and hence thepotential problems that may be caused by the presence of additionalcomplexes in the body of water. Thus the use of a compound containing ahydantoin ring, which has no biocidal effect when used alone, can beused to enhance the purification of the water without introducing waterpurification agents that of themselves may render the water unsuitablefor drinking.

While both a source of silver ions and a compound containing a hydantoinring can be added in tablet form or the like as illustrated in FIG. 6 afeature of the invention is that the compound containing the hydantoinring may be added separately and in various quantities dependent on thestate of the non-potable water. As the water bottles are transportableto different locations there may be some geographical locations wheremore purification is required and somewhere less water purification isrequired. In some instance the source of silver ions, for example silverchloride, which is supported by a carrier, may be used as the sole waterpurification material. If the person is traveling to a differentgeographical location where the water is less potable the use of silverchloride or the like as the water purification material in thenon-potable water may be inadequate because of the natural limits of thesolubility of silver. To increase the effectiveness of the waterpurification material one can add a quantity of a compound containing ahydantoin ring. For example, a tablet containing a hydantoin ring suchas DMH can be added to the container to increase the solubility ofsilver in the water in the container and hence the effectiveness of thewater purification material. The tablets may can be sized to increasethe solubility of silver to predetermined levels and hence theeffectiveness of the water purification material to different levels.

A further feature of the invention is that in household applications indifferent geographical regions one may use the same water purificationagent i.e. a source of silver ions such as silver chloride however theamount of compounds containing a hydantoin ring i.e. DMH may be adjustedto levels to bring the silver solubility up to levels where the silveralone is effective in purifying the non-potable water. Consequently, thelevel of effectiveness of the water purification material can beenhanced to the desired level by the addition of a compound containing ahydantoin ring even though the compound containing a hydantoin ringlacks any biocidal properties.

FIG. 7 shows still another example of a water purification device foruse in household where one may want more than a container of water. Forexample where many members of a family or a community require a sourceof purified drinking water. In this embodiment the water container 61 issupported by a set of four legs 62. Located at the bottom of container61 is a source of silver ions and a compound containing a hydantoin ring64, for example DMH, to generate silver ions to kill the harmfulorganism in the non-potable water. Attached to the bottom of container61 is an extension 69 which is shown partially in section to reveal afilter media therein. A valve housing 65 includes a valve handle 67 thatcan be opened to allow water to flow through spigot 66. Typicality inthis embodiment a few gallons of water can be purified.

As FIG. 7 shows one may have household water purification system forinsitu generation of potable water comprising a portable containerhaving an opening in the container for introducing water to be purified.The water purification material which may comprise a source of silverions and a compound containing a hydantoin ring where the compoundcontaining the hydantoin ring is used to elevate the solubility of thesilver ions in the water to be purified to a level above the normalwater solubility of silver ions in the non-potable water. The outlet forthe potable water may a faucet or spigot as shown in FIG. 7 or theoutlet and the inlet may be the same in which case the water can bedrawn or scooped out of container 61 on an as needed basis.

A further benefit of the invention described herein is that one canadjust the silver solubility in water to respond to the waterconditions. That is, if the non-potable water contains relatively fewharmful organisms little or no DMH may be used. On the other hand if thewater contains substantially amount of harmful organisms, which can notbe effectively controlled with the use of the metal ions alone, one canadd DMH or any other compound containing a hydantoin ring until thesolubility of silver in the water increases to a level where the silverions can quickly and effectively bring the non-potable water to apotable state.

Thus a feature of the invention is a novel method of purifying water ina human portable container by introducing a non-potable water, a sourceof silver ions and a compound containing a hydantoin ring into thecontainer to increase the natural water solubility of silver ions; andconverting the non-potable water into potable water by exposing thenon-potable water to the source of silver ions and the compoundcontaining a hydantoin ring. The method of purifying water may includeintroducing sufficient compound containing a hydantoin ring such as DMHinto the nonpotable water to increase the solubility of silver ions to alevel sufficient to purify the non-potable water. For example, in theparticular geographical area one may increase the level of silversolubility in excess of 50 ppb. If desired, once the non potable waterbecomes potable one has the option of removing silver ions from thepotable water with an ion exchange resin to reduce the silver ions to adesired level.

FIG. 8 shows an example of a dispenser 70 for use with non-potable waterthat may be held in a human portable container RA daily drinkingtherefrom by one or more persons. Typically, such portable containersmay hold as little as a gallon of non-potable water or they may containmany gallons of non-potable water as long as the container may becarried and/or transported to different location by a single userwithout the aide of a machine. Dispenser 70 is well suited forpurification of small amounts of non-potable water found in open waterlakes although it may be used with other sources of non-potable water.Lake water, which is used for human consumption, may be found in variousgeographic regions but oftentimes is prevalent in wilderness areas,particularly in areas where there are lake cabins and no wells fordrawing water. In these areas a bucket or pail of non-potable water maybe retrieved from the lake and carried to a cabin where the non-potablewater is purified for drinking. To purify a portable container ofnon-potable water dispenser 70 is merely placed in the pail ofnon-potable water.

FIG. 8 shows the dispenser 70 comprise a spherical housing 71 with aplurality of openings 73 therein for ingress and egress of water.Housing 71 is typically made from a polymer plastic or the like to forman enclosure for the water purification material. In this example thewater purification material comprises a source of silver ions 74 and acompound containing a hydantoin ring 75. The combination increases thesolubility of the silver ions in the non-potable water to quicklyconvert the non-potable water in the container into potable waterwithout the aid of additional water purification agents. With thisparticular dispenser one need only draw a pail of water and place thedispenser with the water purification material in the pail ofnon-potable water. The dispenser and the water purification may be sizedfor use with only a single pail of water or it may be sized for extendeduse. If the dispenser is sized for multiple uses the person would removethe dispenser from the pail when empty, again fill the pail withnon-potable water and then place the dispenser 70 in the pail ofnon-potable water to convert the non-potable water into potable water.This type of in-situ purification is well suited for portable containersthat have a maximum holding capacity of 15 gallons or less andpreferably a maximum holding capacity of five gallons or less since suchcontainers can be readily carried by one person without the aide of amachine as he or she retrieves a container of non-potable water.Although well suited for small containers if desired the dispenser maybe used with larger containers for example in containers which may holdup to 2000 gallons of water. In such cases two or more dispensers may beused to purify the non-potable water in the container.

In the example shown the dispenser 70 includes a floatation chamber 76which allows the dispenser 70 to float while the submerged portion ofthe dispenser containing the water purification material 74, 75 is incontact with the non-potable water through the ingress and egress ofwater through apertures 73.

This type of dispenser is also well suited for placement in communitycontainers such as container 60, which is shown in FIG. 7. An advantageof the floating dispenser is that one can quickly tell of thenon-potable water has been converted to potable water by the merepresence of the floating dispenser. It should be pointed out thatalthough a hollow spherical housing 70 is shown other shapes for thedispenser housing may be used without departing from the spirit andscope of the invention.

FIG. 9 shows a water purification system 80 that converts non-potablewater to potable water by pumping non-potable water through the waterpurification material. System 80 includes a container 81 withnon-potable water 82 located therein. One end of a pipe 83 extends intothe non-potable water 82 and the other end into a water inlet in anelectric pump 84 with pump 84 having electrical leads 84 a and 84 b forreceiving power to operate pump 84. The water pump outlet 85 connects toa housing 86, which contains the water purification material asdescribed hereinabove. As the non-potable water is pumped throughhousing 86 the water is purified. That is the water purificationmaterial comprising a source of silver and a compound containing ahydantoin ring converts the non-potable water into potable water. Thepotable water then flows from housing 86 through pipe 87, which directsthe potable water 91 into container 90. The potable water 91 can then bedrawn as needed from the container 90 through a valve 92 and spout 93.

It is envisioned that the electric water pump 84 may be powered by solarpower or other sources of available power. If desired, a mechanical pumpmay be used to draw the non-potable water from the container 81. Whilelarger quantities of non-potable water can be converted into potablewater a feature of the invention herein that allows one to quicklyconvert small quantities of non-potable water into potable wateron-the-go. For example container 90 may be a drinking glass or othertype of drinking container to allow a person to drink the potable wateronce it has been discharged from pipe 87.

1.-13. (canceled)
 14. A method of purifying water immediately prior toconsumption of the water comprising; introducing a non-potable water,where the non-potable water may contain halides, into a housingtransportable by a single user without the aide of a machine whenfilled; bringing the non-potable water into contact with a source ofsilver ions and a compound containing a hydantoin ring to increase thenatural water solubility of silver ions in the non-potable water; andconverting the non-potable water into potable water by exposing thenon-potable water to the source of silver ions and the compoundcontaining a hydantoin ring prior to consuming the potable water. 15.The method of purifying water of claim 14 wherein introducing thecompound containing a hydantoin ring comprises introducing sufficientDMH into the nonpotable water to increase the solubility of silver ionsin the non potable water to a level in excess of the natural watersolubility of silver ions and removing silver ions from the potablewater with an ion exchange resin to reduce the silver ions in thepotable water before ingesting the potable water.
 16. The method ofpurifying water of claim 14 wherein the step of introducing a source ofsilver ions into the water container and a compound containing ahydantoin ring into the water comprises placing a tablet having a sourceof silver ions and compound containing a hydantoin ring in the containerand the container comprises a hand held container.
 17. The method ofpurifying water of claim 14 including the step of adjusting the naturalwater solubility of silver ions by adding a compound containing ahydantoin ring where the compound containing a hydantoin ring lacks anybiocidal properties and pumping the water through the water purificationmaterial.
 18. The method of purifying water of claim 14 including thestep of directing the potable water through a filter media to decreasethe level of silver ions in the potable water after the non-potablewater has been purified with the water purification material.
 19. Themethod of purifying water of claim 18 wherein the step of directing thewater through a filter media comprises direction the water through anion exchange filter before ingesting the potable water.
 20. The methodof purifying water of claim 14 wherein the source of silver ionscomprises silver chloride and the compound containing a hydantoin ringlacks biocidal properties.